No, I'm going to disagree with that. A google-free Android is still a very useful device (compared to a notional Nokia 6310i dumbphone benchmark). Using open-source apps you can do email, browse the web, play media files, navigate with Openstreetmap and countless other genuinely useful things without having to rely on a third-party service[1]. It's the closest thing you're going to get to an open smartphone.
Sure, there's functionality that you won't have (google calendars, for example), and there's obviously an amount of hoop-jumping required to actually install apps without access to the Play store, but we're talking about people who've rooted and re-flashed their phone already.
[1] Well, maybe not email. But you could host it yourself, or pay an ISP to host it for you, or use an account provided by an employer, rather than sell your soul to a marketing company for it.